Every day, thousands die worldwide due to infections from waterborne bacteria and viruses. Death typically results from acute dehydration, malnutrition, or other related complications. The majority of victims are young children or elderly people that live in economically impoverished countries. In these regions, contaminated surface water sources and poorly functioning municipal water distribution systems lead to the transmission of waterborne bacterial and viral diseases. Although the problem is particularly bad in impoverished countries, population groups in developed countries, such as residents in remote rural areas of the United States with poor water treatment and delivery systems, are also at risk. In addition, campers and hikers who do not have access to treated water also commonly fall victim to waterborne bacterial and viral infections.
Conventional centralized water treatment and distribution systems can be very expensive and take years to construct. Furthermore, it is often impractical to provide centralized water treatment in sparsely populated areas. Therefore, providing at-risk groups with potable water requires innovative practical solutions such as, for example, point-of-use disinfection. In one disinfection method, ultraviolet (“UV”) radiation having wavelengths in the range of 200 to 300 nm are used to kill disease-carrying microorganisms in water. UV radiation has been found to deactivate a broad spectrum of pathogenic contaminates from amoebic-sized microorganisms to bacteria, algae and viruses. Water purification by ultraviolet radiation provides numerous advantages over other currently available water treatment methods. For example, UV water purification systems do not require chemicals nor do they require expensive filters.
Existing UV water purification systems are often large installed flow-through systems serving a large number of people. However, in recent years, a number of smaller portable UV water purification systems have become available for use by individuals. Portable UV water purification systems use fluorescent tubes for emitting UV light into the water. A quartz cover is often provided around the fluorescent tube to protect the light source from mechanical shock and to electrically insulate the light source from the water being disinfected. Quartz covers are commonly used because it has been found that quartz is transparent at germicidal UV wavelengths, such as, around 254 nm.
Existing portable UV water purification systems also include electronic circuitry for driving the fluorescent lamp. These devices and their circuits are often heavy and include multiple batteries in order to power the device and as such will sink if released into the liquid being treated. Furthermore, they must be affixed to the containers of liquid they are treating or otherwise held in place therein. As a result many containers are not viable candidates for treatment with such a device. Finally, point-of-use devices are generally small and cannot reach into the depths of a large container, limiting their usefulness to small storage and drinking containers.
Due to the costs associated with existing UV water purification systems, a need exists for an improved water purification system that requires fewer components and is easily affordable to large segments of the population. It is desirable that such a system be rugged in construction and easily transportable for disinfecting drinking water in regions where water purification is not readily available. It is also desirable that such a device be lightweight, compact, and easy to use. The present invention addresses these needs.